1. Field of the Invention
The present invention is broadly concerned with improved sizing apparatus of the type used for packaging of flowable materials such as meat into accurately sized, individually encased portions. More particularly, the invention pertains to a sizing apparatus which produces encased portions wherein the casings are incompletely or "loose" filled, while at the same time ensuring that the meat or other flowable material is substantially evenly spread throughout the length of the loosely filled casing. Such evenly distributed, loose-filled casings are used in the production of meat products having non-circular cross-sections, e.g., sausages or luncheon meats of oval or square cross-section.
2. Description of the Prior Art
Many products such as sausages, luncheon meats, hamburger or other comminuted materials are packaged in elongated casings. For example, casing material may be stuffed with a luncheon meat emulsion, which is thereafter cooked, removed from the casing and sliced. Commercial sizing devices have been proposed in the past for high-speed stuffing of casing material and termination of the casing ends, typically through the use of mechanically set clips. For example, U.S. Pat. No. 5,104,348 describes a very successful sizer apparatus designed for this purpose. Generally speaking, sizers include an elongated, tubular stuffing horn having a rearward end adapted for coupling to a meat pump, with an opposed forward end adapted to receive casing material, either as individually applied casings or in elongated, shirred form from which multiple casing sections can be successively drawn. A clipping device is situated adjacent the discharge end of the horn for clipping the casing material and completing the casings as they are formed. In practice, meat is delivered via the pump into the horn and out the discharge end thereof, thereby pulling casing material off of the horn as the meat emerges. As each discrete portion of meat is delivered and encased, the clipping device is operated to clip the terminal ends of the casings.
If the desired end product from a given sizing operation is to have a circular cross-section, the sizing devices of the prior art are completely suitable. That is, the casings are substantially filled throughout the lengths thereof and assume a maximum expanded diameter in excess of the internal diameter of the sizer horn. The only real consideration in such cases is to ensure that the sizer creates accurate portion weights, package-to-package.
On the other hand, many producers desire to make end products having square, oval or some other non-circular cross-sections. In these instances, conventional practice has been to create packages wherein the casing sections employed are loose-filled, i.e., the volume of meat in each section is less than the internal volume of the unexpanded casing section. Such loose-filled casings can then be placed in an appropriate mold or other support having the desired final configuration, whereupon the meat may be cooked to assume this desired shape.
The practice of creating loose-filled casings creates a significant problem in its own right. Specifically, as the meat product emerges from the horn, there is a tendency for the meat to fill and expand the adjacent, forwardmost section of the casing to its fullest extent, leaving a completely unfilled "tail" of casing downstream of the filled casing section. It is then necessary to grasp and manipulate each of these packages individually, and manually knead and shift the meat product within the casing so as to more or less evenly distribute the meat throughout the length of the casing. This hand labor is relatively time consuming and arduous, and represents a real bottleneck in an otherwise highly automated packaging line.
Accordingly, there is a real and unsatisfied need in the art for an improved sizer apparatus and method which is capable of producing loose or incompletely filled casings having the product therein substantially evenly distributed along the lengths of the casings, while eliminating the need for extensive handling and manipulation of the casings.